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A041547 Denominators of continued fraction convergents to sqrt(291). 2
1, 17, 579, 9860, 335819, 5718783, 194774441, 3316884280, 112968839961, 1923787163617, 65521732402939, 1115793238013580, 38002491824864659, 647158154260712783, 22041379736689099281, 375350613677975400560, 12783962244787852718321 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..200

Index entries for linear recurrences with constant coefficients, signature (0,580,0,-1).

FORMULA

G.f.: -(x^2-17*x-1) / (x^4-580*x^2+1). - Colin Barker, Nov 18 2013

a(n) = 580*a(n-2) - a(n-4) for n>3. - Vincenzo Librandi, Dec 20 2013

MATHEMATICA

Denominator[Convergents[Sqrt[291], 40]] (* Harvey P. Dale, Apr 20 2012 *)

CoefficientList[Series[(1 + 17 x - x^2)/(x^4 - 580 x^2 + 1), {x, 0, 30}], x] (* Vincenzo Librandi, Dec 20 2013 *)

PROG

(MAGMA) I:=[1, 17, 579, 9860]; [n le 4 select I[n] else 580*Self(n-2)-Self(n-4): n in [1..40]]; // Vincenzo Librandi, Dec 20 2013

CROSSREFS

Cf. A041546, A040273.

Sequence in context: A191865 A249862 A056771 * A041544 A202407 A009709

Adjacent sequences:  A041544 A041545 A041546 * A041548 A041549 A041550

KEYWORD

nonn,frac,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from Colin Barker, Nov 18 2013

STATUS

approved

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Last modified February 22 15:52 EST 2019. Contains 320399 sequences. (Running on oeis4.)